The Benefits and Applications of Alloy Steel Pipes

​The main applications of alloy steel pipes is power station, nuclear power plant, high pressure boiler, high temperature superheater and re-heater coil etc. of high temperature pipeline and equipments.

The advantages of alloy steel pipes: 100% recycled, it is suitable for the national strategy of environmental protection, energy-saving and resource-saving. Therefore, the national policy encourages the expansion of the high pressure alloy steel pipe applications. At present, the proportion of the total alloy steel tube is half of the developed countries. The applications of alloy steel pipe provide a broad space for the industry development. According to the research of the China association of special steel alloy pipe expert group, our country’s high pressure alloy steel pipe material demand grows by an average of up to 10-12%.

How do I choose which alloy steel to use? Selecting the right alloy  for a specific application is vitally important in order to achieve a sustainable solution, while cost aspects must also be taken into consideration. There are several stages when material selection needs to be made: new applications and equipment, new processes and process changes, exchange of material due to poor performance, exchange of existing material to minimize cost

To make the right material selection it is important to get a full picture of the service conditions the steel will face. The first aspects to consider could be material related, for example: corrosion resistance, mechanical strength, fabric ability, physical properties, surface aspects

ASTM A355 Seamless Alloy Steel Pipe

Astm a335 standard specication for seamless ferritic alloy-steel pipe for high-temperature service. This specication covers nominal(average) wall seam-less alloy-steel pipe intended for high-temperatureservice.Pipe ordered to this specication shall be suitable for bending,anging(vanstoning),and similar forming operations,and for fusion welding.Selection will depend upon design,service conditions,mechanical properties,andhigh-temperature char-acteristics. 

Chemical Composition  Grade  C  Mn  P  S  Si  Mo  P1  0.10-0.20  0.30-0.80  0.025  0.025  0.10-0.50  0.44-0.65  P2  0.10-0.20  0.30-0.61  0.025  0.025  0.10-0.30  0.44-0.65  P5  0.15max  0.30-0.60  0.025  0.025  0.50max  0.45-0.65  P5b  0.15max  0.30-0.60  0.025  0.025  1.00-2.00  0.45-0.65  P5c  0.12max  0.30-0.60  0.025  0.025  0.50max  0.45-0.65  P9  0.15max  0.30-0.60  0.025  0.025  0.25-1.00  0.90-1.10  P11  0.05-0.15  0.30-0.60  0.025  0.025  0.50-1.00  0.44-0.65  P12  0.05-0.15  0.30-0.61  0.025  0.025  0.50max  0.44-0.65  P15  0.05-0.15  0.30-0.60  0.025  0.025  1.15-1.65  0.44-0.65  P21  0.05-0.15  0.30-0.60  0.025  0.025  0.50max  0.80-1.06  P22  0.05-0.15  0.30-0.60  0.025  0.025  0.50max  0.87-1.13  P23  0.04-0.10  0.10-0.60  0.030max  0.010max  0.50max  0.05-1.30 Mechanical Properties  Mechanical properties  P1,P2  P12  P23  P91  P92,P11  P122  Tensile strength  380  415  510  585  620  620  Yield strength  205  220  400  415  440  400